Connector assembly for electrical apparatus

ABSTRACT

An angle connector for high-voltage rotary-field (three-phase) transformers in which a cast synthetic resin jack body is received in the transformer housing and forms at its end remote therefrom a socket extending at right angles to a bolt, pin or rod to which the socket is affixed, both socket and rod being imbedded in the insulating composition. A plug is fitted into the socket and is potted in a frustoconical sleeve which is flanged to a sleeve of the jack body.

United States-Patent [56] References Cited UNITED STATES PATENTS 2/1942Rogers Inventor Reinhold lllies Wurselen, Germany 887,1 1 1 2,273,538339/143 3,146,301 8/1964 Logan 339/143 5 3,466,593 9/1969 Arndt et 21].339/61 R 3,474,386 10/1969 Link...... 339/6OR FOREIGN PATENTS 7/1962Great Britain...

[21 Appl. No. [22] Filed Dec. 22,1969 [45] Patented Nov. 23, 1971 [73]Assignee Firma Neidecker & Co. Basel, Switzerland [32] Priority Dec. 21,1968 [33] Germany 1 Primary Examiner.1ose Almrney-Kar1 F. Ross ph H.McGIynn RICAL 'PATENTEDuuv 23 I97! 3,622 940 sum 1 0F 2 F. 3 b, s 7 H iH a s! 11 Hi Em 70 mi- 3 73 W f2 a; fig H 1 m /5 6a i HI INVI'INI ()RfRe inhold II/ies BY W ' Attorney PATENTEDuDv 23 I97! 3,622,940

SHEEI 2 OF 2 Reinhold III/es lNVIiN'l'UR.

rl jams Attorney,

CONNECTOR ASSEMBLY FOR ELECTRICAL APPARATUS FIELD OF THE INVENTION Thepresent invention relates to electrical connectors and, moreparticularly, to plug-and-jack connectors for high-voltage electricalequipment, especially high-voltage rotary-field 3 phase transformers.

BACKGROUND OF THE INVENTION While a wide variety of plug-and-jackconnectors is known for electrical systems, the field of high-voltageconnectors is more or less limited to rather massive insulatedstructures capable of withstanding thesevere electrical and mechanicalstress to which such connectors are subjected. In fact, it is not commonpractice to provide plug-and-jack connectors for high-voltagetransformers and the like because of the inability of prior artconnectors of this type towithstand the tendency toward breakdown atelevated electrical potentials, attack by the insulating media(transformer oils and chlorinated aromatic carbons), and thermalstresses arising as a result of heat generated at the connection orwithin the apparatus.

It has also been proposed to provide plug-and-jack connectors forrotaryfield high-voltage transformer and in which the jack body has aright-angle or L-shaped configuration affording an inner chamber and/orpassage through which air can flow. The plug member of this type forms ajunction with the end of the electrical conductor or cable and the spacearound the cable plug and the inserted cable end is filled with a liquidinsulating material, e.g., transformer oil or the chlorinated aromatichydrocarbons commonly used to insulate electrical apparatus subject tohigh-voltage breakdown.

It has, however, been found that considerable difficulty is encounteredin such systems because of the problem of sealing the liquid insulatingmaterial in the connector. As a result, it has often been necessary tointroduce the cable from above and this effort to prevent leakage of theinsulating liquid has often proved ineffective and certainly has limitedthe ability to use the prior art plug-and-jack connector.

OBJECTS OF THE INVENTION It is, therefore, the principal object of thepresent invention to provide an improved plug-and-jack connector forelectrical apparatus wherein the aforedescribed disadvantages can beobviated.

It is another object of the invention to provide an improved angleconnector for electrical apparatus which is capable of withstandingelectrical, mechanical and thermal stress and which may be used withliquid insulation systems, operating with transformer oil or the like,without unwanted leakage.

Still another object of the invention is the provision of an improvedbut simplified and relatively inexpensive electrical connector forright-angle junctions between an electrical cable and a high-voltagerotary-field transformer SUMMARY OF THE INVENTION These objects, andothers which will become apparent hereinafter, are attained in aplug-and-jack connector for high-voltage rotary-field transformers,which comprises a jack or socket member fitted into a wall of thetransformer and cast of a low mass (massless or low density)electrically insulating synthetic resin, the jack member preferablyextending through the wall of the rotary field transfonner in accordancewith the practice customary heretofore with such connectors; alongitudinally extending bolt, pin or rod of metal extends through andis imbedded in the body of synthetic resin material and anchors at thefree end of the rod remote from the interior of the transformer, asocket member which is also imbedded in the synthetic resin material andis open away from its junction with the rod. This socket may be of themulticontact type described in the commonly owned U.S. Pats. No.3,453,587, No. 3,296,575 or No. 3,2 l4,72l and lies at an angle,preferably a right angle, to this socket.

Removably connectable with the insulating body thereof or integral withthis body, there is provided, in accordance with this invention, asleeve or duct member into which the forwardly projecting end of a plugassembly may be seated with clearance, the tip of the plug assemblybeing formed with a plug member, complementary to and receivable in thesocket member to establish electrical connection. The plug assembly alsocomprises, in accordance with the invention, a frustoconical sleevehaving at its forward end an annular transverse flange which issealingly bolted to the annular transverse flange at the free end of theaforementioned sleeve, whereby the interior of the latter and the spacetherein surrounding the cable, is closed. There is also provided anannular compartment converging away from the socket member, between theinner wall of the frustoconical sleeve and the outer wall of the cable,which is filled with an electrically insulating composition which, uponsetting, forms a seal for the interior of the connector, therebypermitting .the latter to receive transfonner oil or some otherinsulating liquid.

The plug-and-jack connector for electrical apparatus of the presentinvention thus comprises a jack body which is cast or molded of a s'nthetic resin having high-voltage breakdown characteristics, suited tothe particular installation, and serving to fix a socket member which isimbedded in a head portion of the jack body. Unitarily andmonolithically formed with the head of the jack body, is a solid shankportion which is received in and traverses a wall of the electricalapparatus with which the connector is used. A rod passes centrallythrough this cylindrical shank portion and serves as a terminal for theconnector.

In addition, the jack body is provided with a sleeve member which shollow and likewise is formed of a synthetic resin with high-voltagebreakdown characteristics, the sleeve portion being closed at its endproximal to the head portion of the jack body but open at its free endremote therefrom.

The sleeve portion, moreover, is of cylindrical configuration and hasits axis extending perpendicularly to the axis of the shank portion, andmay be monolithically unitarily with the head portion and removablyaffixed thereto. In the former case, the socket member which is embeddedin the jack body, may open, axially along the sleeve portion throughwhich the elongated extension of the plug is designed to lie when theplug member, at the end of the extension, is inserted into the socketmember. An open airspace is provided between the extension of the plug,which may be a potted portion of the cable to increase its rigidity.

At the free end of the sleeve vided a closure portion in the portion,moreover, there is proform of a frustoconical sleeve which convergesaway from the open end of the sleeve portion but is connected thereto ata pair of confronting flanges formed respectively on the frustoconicalsleeve and upon the free end of the sleeve portion of the jack body. Asealant of the castable type, e.g., a foamed elastomeric cellularpolyurethane composition, may be cast in the space between the innerwall of the frustoconical member and the portion of the cable and/orplug assembly received in this frustoconical sleeve.

The external surfaces of the jack the and the sleeve portion areadvantageously metallized and, when the sleeve portion is removablyreceived in the heat portion of the jack body, there are provided matingcoaxial formations, preferably surrounding the socket member andconverging in the direction of insertion of the plug, to center theassembly. In this case the plug member may be formed in the wall of thesleeve portion which is to be fixed to the'head of the jack body.

The aforedescribed system, according to the invention, makes use of alightweight, low-mass solid body of cast synthetic resin and arelatively dense but small socket member and connecting rod. It has theimportant advantage that the connector may be used at practically anyangle (i.e., with the plug extending in substantially any direction fromthe axis of the shank) since the shank is anchored in the wall of thetransformer and the orientation is not material. Moreover, the connectormay be disposed substantially anywhere on the transformer housing andmay be made without expensive apparatus to the desired shank lengthsdepending upon the wall thickness. Moreover, it has been found to theadvantageous to constitute the plug assembly as standardized orfixed-configuration members, regardless of the configuration of the jackbody with which the plug assembly is to be used. It is only significantthat the socket member embedded in the jack body be standardized tocorrespond to the plug members. Furthermore, with relatively simple moldarrangements, the jack body may be cast in place on the wall of thetransformer.

The jack body, according to this invention, may be provided with anopening in the direction of the axis of its shank portion to accommodatea preformed or standard plug inserted in the axial direction or plugmembers specially designed or adapted to fit the socket member at theopen end of the head of the jack body. In this case, the socket memberhas its mouth open along the axis of the shank portion, perpendicular tothe wall in which the jack body is mounted.

Preferably, however, the jack portion is used with a sleeve portion ofthe aforedescribed type wherein, at its closed end, the sleeve portioncarrying a plug which is received in the socket member and interfitswith the head of the jack body so as to constitute a right-angleextension thereof. The first type of connection is most common when thecable is a synthetic resin-covered cable and is relatively flexible,whereas the second type may be used when the cable is less flexible andis a paper-composition impregnated insulation cable. Such cables aresensitive to dislocation by bending and are anchored to the fixedlypositioned plug at the end of the sleeve portion and may be anchored tothe open end of the latter as well by the closure member previouslydescribed.

DESCRIPTION OF THE DRAWING The above and other objects, features andadvantages of the present invention will become more readily apparentfrom the following description, reference being made to the accompanyingdrawing in which:

FIG. 1 is a fragmentary vertical section, partly in elevation, of anelectrical connector embodying the invention;

FIG. 1A is a view similar to FIG. I of a detail, showing the plugassembly partly removed;

FIG. 2 is a view similar to FIG. 1 of a portion of another embodiment ofthe invention; and

FIG. 2A is an end view of the jack body after removal of the sleeveportion thereof.

SPECIFIC DESCRIPTION In FIG. 1, there is shown the wall I of atransformer of the rotary-field or three-phase type which is filled withtransformer or insulating oil and is provided with the connectingassembly of the present invention. It will be understood that threeconnectors of the type illustrated in FIG. I are commonly used.

The connector comprises a jack body 2 monolithically cast from an epoxyresin having high-voltage breakdown characteristics and comprising acylindrical shank portion 3 in which the connecting rod 4 is embeddedaxially. The rod terminates at the head 3a of the jack body in aninternally threaded sleeve 40 into which the threaded projection 50 of asocket member 5 is screwed. The socket member 5 is likewise embedded inthe synthetic resin material of the jack body. The inner cavity 512 ofthe socket member, whose outwardly flared mouth 50 opens along the plugaxis perpendicular to the axis of the rod 4, is formed with springlayers or elements of the multicontact type described and claimed in theabove-identified patents.

The head 30 of the jack body is located externally of the transformerand the socket member 5 is spaced outwardly of the wall thereof. Thebody 2, 3, 30 may, of course, be cast in place of preformed tocorrespond to the requirements of the particular transformer and thusmay vary from transformer to transformer according to the physical andelectrical requirements. However, the multicontact socket member 5 maybe a standardized unit as illustrated also in FIG, 2, and willaccommodate standardized plugs or adapters provided with standardfittings cooperating with the socket member.

From the head 3a, a sleeve portion 3b extends at right angles to the rod4 and terminates in an annular transverse flange 10 at the open end ofthis sleeve portion. It has been found to be desirable to design thesleeve portion 312 so as to provide a cylindrical annular space 14around the plug 6 close to the socket member 5, the chamber wideningoutwardly at Ma away from this cylindrical portion. The plug assembly isshown to comprise a cable 6a which is clamped at 6!) in the plug member6, the tip 7 of which is receivable in the Multicontact socket member 5.A centering member is provided at 8 to guide the plug, while a cone9(e.g. of sintered iron) surrounds the plug 6 to control the electricalfield in the usual manner. A ground lead 15 is shown to emerge from theassembly.

A sealing ring 11 is clamped between the flange l0 and the confrontingflange 10a of a frustoconical closure 12 which converges away from thesocket and has the space between the jack and the inner wall of thisclosure filled with a cast synthetic resin material which, upon thesetting, seals the closure member 12 to the plug and enables the closuremember and plug to be removed together. Screws 10b secure the closuremember to the sleeve portion 3b. The sealing mass is preferably anelastomeric cellular synthetic resin such as a foamed polyurethane. Itwill be understood that the connector illustrated in FIGS. 1 and 1A isindependent of orientation of structure so that it may be positioned inany direction upon the outer wall of the apparatus. Consequently, thedimensions of the connector can be selected in accordance with optimumpositioning and orientation requirements.

Whereas the system illustrated in FIGS. 1 and IA is designed primarilyfor so-called plastic insulated cables, the system of FIGS. 2 and 2A isprimarily designed for use with impregnated-insulation cables which aremuch more sensitive to bending and distortion.

In this embodiment the shank portion 18 the jack body is cast of anepoxy resin having a high-voltage breakdown characteristic and embed theconnector rod 17 and the internally threaded sleeve 17a which is affixedthereto.

The standardized Multicontact socket 16 has its shank 16a threaded intothe sleeve 15a and is also embedded in the lightweight mass 18 ofinsulating, hardenable casting material. The flange of the head of thejack body is formed by an annular flange 20a at the base of anexternally cylindrical, but inwardly frustoconical formation 20 whichconverges in the direction of the axis of the jack body in the directionin which the plug member 23 is inserted. The mating formations of thesleeve portion 19 are illustrated at 2! and 21a and consist,respectively of a frustoconical boss 21 rising from the wall 21b of thesleeve portion 19, and a frustoconical recess 21a complementary to theformation 20. A bayonet coupling or screw arrangement may be provided toconnect the sleeve portion to the cast body 18 as shown at 20b.

In the recess 21c enclosing the projecting end of the socket member 16,there is provided a plug 23 whose flange 23a is seated against theright-hand side of the wall 21b and is threaded at 23b into a lug 23chaving a flange 23d resting against the inner surface of the wall 21b.The conductor 6a of the cable is received in 18 lug 23c and may be castor soldered in place. An characteristic is provided at the upper end ofthe sleeve I9 and is closed by a plug 25 to enable the space 24surrounding the electrical plug 22 to be filled with an elastomericsynthetic resin such as the polyurethane used to bond the closure sleeveto the lower portion of the plug as previously described in connectionwith FIG. 1. The lower end of the sleeve 19 is provided with a flangeand a seal arrangement as illustrated at 10 and 11 in FIG. 1 while theclosure configuration may be that shown at 12 in this Figure.

The interfitting formations 20, 21 form a labyrinth seal at the junctionof the plug 23 with the socket member 16, thereby increasing anyconductive path between the exterior and the exposed conductive membersand limiting accidental short-circuiting or leakage from the junction.in place of a synthetic resin mass, the filler for the space 24 can be abreakdown-resistant fluid such as chlorinated aromatic hydrocarbons ortransformer oil as used in the transformer. The plug is here representedat 22. In broken lines at 26, there is represented a so-calledcompensating or adapter dome for use when a horizontal plug is to beinserted directly in the socket member 16.

The system illustrated in FIG. 2 and 2A has the significant advantagethat a relatively short plugging distance is provided, this not beingachievable with conventional connectors. After assembly, of course, themembers 18 and 19 may be fixed by the screws 20b.

I claim:

I. A plug-and-jack connector for electrical apparatus, comprising:

a jack body of electrically insulating material having a shank portionreceivable in a wall of said apparatus and a head portion lyingexternally thereof, said jack body being formed with a socket memberembedded in said head portion of said body and a rod connected to saidsocket member and extending through said shank portion while beingembedded in said body; and

a plug body formed with a plug member removably receivable in saidsocket member and connectable to said jack body, said plug body beingformed with an electrical cable connected with said plug member, saidhead portion being formed with an elongated sleeve portion extending atan angle to said shank portion and defining an internal cavityterminating in the region of said socket member, said plug bodyincluding an elongated extension receivable with clearance in saidsocket member and carrying said plug member, and a closure portionsealingly and removably attachable to said sleeve portion remote fromsaid head portion, said closure portion being an annular housingreceiving said cable with clearance, the clearance between said housingand said cable being filled at least partially with a sealing material.

2. The connector defined in claim 1 wherein said material is a cellularelectrically insulating elastic synthetic resin.

3. The connector defined in claim 1 wherein said sleeve portion and saidjack body have metallized surfaces.

4. The connector defined in claim 1 wherein said jack body and sleeveportion are composed of a cast synthetic resin having high breakdownvoltage.

5. The connector defined in claim 1 wherein said head portion is formedwith an elongated sleeve portion extending at an angle to said shankportion and defining an internal cavity terminating in the region ofsaid socket member, said plug body including an elongated extensionreceivable with clearance in said socket member and carrying said plugmember.

6. The connector defined in claim 5 wherein said sleeve portion isdetachably mounted upon said head portion substantially level with saidsocket member, said head portion and said sleeve portion being providedwith mating rotationally symmetrical formations coaxial with said socketmember.

7. The connector defined in claim 6 wherein said sleeve portion isprovided with a wall confronting said socket member, said plug memberextending through and being entered in said wall of said sleeve portion,said cable entered in said wall of said sleeve portion, said cableextending through said sleeve portion and being anchored to said plugmember in the region of said wall of said sleeve member.

8. The connector defined in claim 7 wherein said formations arefrustoconical and converge axially in the direction of insertion of saidplug member in said socket member.

1. A plug-and-jack connector for electrical apparatus, comprising: ajack body of electrically insulating material having a shank portionreceivable in a wall of said apparatus and a head portion lyingexternally thereof, said jack body being formed with a socket memberembedded in said head portion of said body and a rod connected to saidsocket member and extending through said shank portion while beingembedded in said body; and a plug body formed with a plug memberremovably receivable in said socket member and connectable to said jackbody, said plug body being formed with an electrical cable connectedwith said plug member, said head portion being formed with an elongatedsleeve portion extending at an angle to said shank portion and definingan internal cavity terminating in the region of said socket member, saidplug body including an elongated extension receivable with clearance insaid socket member and carrying said plug member, and a closure portionsealingly and removably attachable to said sleeve portion remote fromsaid head portion, said closure portion being an annular housingreceiving said cable with clearance, the clearance between said housingand said cable being filled at least partially with a sealing material.2. The connector defined in claim 1 wherein said material is a cellularelectrically insulating elastic synthetic resin.
 3. The connectordefined in claim 1 wherein said sleeve portion and said jack body havemetallized surfaces.
 4. The connector defined in claim 1 wherein saidjack body and sleeve portion arE composed of a cast synthetic resinhaving high breakdown voltage.
 5. The connector defined in claim 1wherein said head portion is formed with an elongated sleeve portionextending at an angle to said shank portion and defining an internalcavity terminating in the region of said socket member, said plug bodyincluding an elongated extension receivable with clearance in saidsocket member and carrying said plug member.
 6. The connector defined inclaim 5 wherein said sleeve portion is detachably mounted upon said headportion substantially level with said socket member, said head portionand said sleeve portion being provided with mating rotationallysymmetrical formations coaxial with said socket member.
 7. The connectordefined in claim 6 wherein said sleeve portion is provided with a wallconfronting said socket member, said plug member extending through andbeing entered in said wall of said sleeve portion, said cable entered insaid wall of said sleeve portion, said cable extending through saidsleeve portion and being anchored to said plug member in the region ofsaid wall of said sleeve member.
 8. The connector defined in claim 7wherein said formations are frustoconical and converge axially in thedirection of insertion of said plug member in said socket member.